An intrauterine device is a contraceptive. It is worn inside the uterus, potentially for up to five years. An IUD works after conception. It stops a newly fertilised embryo implanting and growing in the lining of the uterus. This teaching model showed students and patients the insertion process. The disposable introducer and IUD are within the plastic model of the female reproductive system. Intrauterine devices became popular in the 1960s and 1970s. However, their use fluctuated during the 1980s due to health scares and litigation. An IUD is now the most inexpensive long-term reversible method of contraception available.